Better display representation for intersection types

I'm not sure if this has been discussed before, but join types are mostly unreadable. I think the type should be prettified somehow before being displayed to the user.

TypeScript Version:

1.8

Code

type T1 = {};
type T2 = {test: number};
type J = T1 & T2;

Expected behavior:

var x: J;
typeof x; // {test: number}

Actual behavior:

var x: J;
typeof x; // {} & {test: number}

使用 TypeScript 1.8 重现所提供的 T1/T2/J 示例，并比较显示的 typeof x 结果。未指定文件或测试，因此请跟踪负责显示交集类型的编译器路径；完成的标准是示例按预期显示 {test: number}。